A Reconstruction of Regional and Global Temperature for the Past 11,300 YearsSurface temperature reconstructions of the past 1500 years suggest that recent warming is unprecedented in that time. Here we provide a broader perspective by reconstructing regional and global temperature anomalies for the past 11,300 years from 73 globally distributed records. Early Holocene (10,000 to 5000 years ago) warmth is followed by ~0.7°C cooling through the middle to late Holocene (<5000 years ago), culminating in the coolest temperatures of the Holocene during the Little Ice Age, about 200 years ago. This cooling is largely associated with ~2°C change in the North Atlantic. Current global temperatures of the past decade have not yet exceeded peak interglacial values but are warmer than during ~75% of the Holocene temperature history. Intergovernmental Panel on Climate Change model projections for 2100 exceed the full distribution of Holocene temperature under all plausible greenhouse gas emission scenarios.

_________________With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none” Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."Albert Einstein

_________________"With every decision, think seven generations ahead of the consequences of your actions" Ute rule of life.“We do not inherit the earth from our ancestors; we borrow it from our children”― Chief Seattle“Those Who Have the Privilege to Know Have the Duty to Act”…Albert Einstein

Lets have a look at some of the facts surrounding this study. Shaun Marcott is a very inexperienced first year PhD. from Oregon State University. Who in the past has publically stated when asked about Mann et al., “Its not robust.” Marcott’s study is a proxy based model smoothing study using 73 sample marine sites that claims to cover 196 million square miles and 11,300 years. Only 73 marine sites that seem to me would proxy ocean temperatures rather than atmosphere temperatures. Now something doesn’t pass the smell test about this. Marcott et al was published according to the link provided on March 8th. A Friday. But Seth Borenstein of AP published a story about this paper on March 7th.

“In the new research, scheduled for publication of Friday (March 8th) in the journal Science.”

Again a day before the release in Science. This is a coordinated effort by all involved here. Two articles written a day before release with details about the study before it was published. This amounts to tabloid climatology. Oh but it gets better. Marcott et al have yet to release any data or materials regarding this paper. Taking advice from Dr. Mann? From the March 12th National Journal.

“Marcott admitted he was apprehensive about charging into the fully-mobilized troll army...” Oh, he sounds like an objective man of science only concerned with the truth doesn’t he?

But wait it gets even better. This study appears to be based upon Marcott’s thesis paper. But, there are key differences in the conclusion of both. First graph is from the thesis.

Second graph is from the released study.

A hockey stick magically appears. This is climate science by press release, pal review, and Science, the AP, and the New York Times promote it as peer reviewed when the researcher refuses to turn over data and material so someone else can attempt to repeat it. This study is no more than a glorified press release. Embarrassing at most. At the least proving this researcher has serious problems with his methodology.

Obama has failed with the carbon tax, cap and trade, but James Hansen said in 2008 that Obama has four years to save the planet. The UN issued another tipping point in 1989. 10 years. Both have passed and we are still here. This movement is a joke. No one believes you. Your desperate. I knew this cause was in trouble when it began to make absolutely everything imaginable was the fault of climate change. At this point the theory ceases to be falsifiable. It has become political theory so it becomes whatever the politicians want it to be. It is certainly not science.

Tick, tick, tick – how long will the new Marcott et al hockey stick survive?

Posted on March 15, 2013 by Anthony Wattsby Anthony Watts

Steve McIntyre writes of the curious uptick in the 20th century, which doesn’t seem to be rooted in reality, or to have been in Marcott’s PhD thesis:

While one expects a difference between NHX and SHX in the Holocene, the remarkable difference between NHX and SHX not just in the 20th century, but in the 19th century is a source of considerable interest. According to Marcott, NHX temperatures increased by 1.9 deg C between 1920 and 1940, a surprising result even for the most zealous activists. But for the rest of us, given the apparent resiliency of our species to this fantastic increase over a mere 20 years, it surely must provide a small measure of hope for resiliency in the future.

Quote:

Guest post by Dr. Don J. Easterbrook

Part I of this series looked at the validity of conclusions for the 11,300 time span covered in Marcott et al. “A Reconstruction of Regional and Global Temperature for the Past 11,300 Years.” This segment (Part II) analyzes conclusions in the Marcott et al. paper in which they contend that “Global temperatures are warmer than at any time in at least 4,000 years” and “Global temperature….. has risen from near the coldest to the warmest levels of the Holocene within the past century.” A heat spike like this has never happened before, at least not in the last 11,300 years”

As in Part I, this segment analyzes the Marcott et al. conclusions using the scientific method of Feynman in which conclusions are checked against well-established data from other sources,. As Feynman points out, if a hypothesis (conclusion) disagrees with observations and data, it is wrong. It doesn’t make any difference how beautiful the hypothesis (conclusion) is, how smart the author is, or what the author’s name is, if it disagrees with data or observations, it is wrong.

Quote:

Guest post by S. Fred Singer

Green forces, eager to promote their theories of global warming, appear to be practicing intellectual recycling. Is this the return of the notorious hockeystick – which, in 2001, was the central dogma of Anthropogenic Global Warming (AGW) believers?

This quasi-religious faith in catastrophic AGW still remains a prerequisite for membership in scientific and media elite circles, even in the face of the failure of earlier (model) predictions of apocalypse to manifest, and the admission by an apostle of the faith that for the past 17 years global temperatures have not increased — contrary to the projections of every climate model.

Yes, everyone follow Wayne's suggestion and go to WUWT and read all about it.

_________________"With every decision, think seven generations ahead of the consequences of your actions" Ute rule of life.“We do not inherit the earth from our ancestors; we borrow it from our children”― Chief Seattle“Those Who Have the Privilege to Know Have the Duty to Act”…Albert Einstein

Yes, everyone follow Wayne's suggestion and go to WUWT and read all about it.

No, I do not suggest anyone read the ex-weatherman's blog for any real information. I did point out that even such a poor source of information did not support your claim of the data not being released. Since, you clearly were so wrong on that point why would anyone want to take the rest of your points seriously without a lot of supporting evidence?

When you cannot even get blog science to support your claims you really have no support.

Quote:

Guest Post by Willis Eschenbach

I don’t know what it is about proxies that makes normal scientists lose their senses. The recent paper in Science (paywalled of course) entitled A Reconstruction of Regional and Global Temperature for the Past 11,300 Years” (hereinafter M2012) is a good example. It has been touted as the latest hockeystick paper. It is similar to the previous ones … but as far as I can see it’s only similar in how bizarre the proxies are.

Nowhere in the paper do they show you the raw data, although it’s available in their Supplement. I hate it when people don’t show me their starting point. So let me start by remedying that oversight:

_________________With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none” Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."Albert Einstein

I think that the conclusions in the Marcott et al. 2013 should be revised to indicate that the 20th Century uptick that many blogs were concerned about was not statistically robust.

It's an interesting analysis for the Holocene Warm Period, but to focus on the 20th Century uptick of the reconstruction doesn't make much sense when the authors themselves confirmed that the uptick in the 20th Century was not statistically robust.

I think that the conclusions in the Marcott et al. 2013 should be revised to indicate that the 20th Century uptick that many blogs were concerned about was not statistically robust.

It's an interesting analysis for the Holocene Warm Period, but to focus on the 20th Century uptick of the reconstruction doesn't make much sense when the authors themselves confirmed that the uptick in the 20th Century was not statistically robust.

The reconstruction smoothing resolution would not have made it the best choice, but since we have instrumental records that cover the last ~150 years, well, there is no real need to worry with the reconstructed data at that point. If we had such instrumental data for the whole period we would not be dealing with reconstructions at all. Unless you are saying the reconstruction and instrumental records do not support each other in some manner?

Q: How do you compare the Holocene temperatures to the modern instrumental data?

A: One of our primary conclusions is based on Figure 3 of the paper, which compares the magnitude of global warming seen in the instrumental temperature record of the past century to the full range of temperature variability over the entire Holocene based on our reconstruction. We conclude that the average temperature for 1900-1909 CE in the instrumental record was cooler than ~95% of the Holocene range of global temperatures, while the average temperature for 2000-2009 CE in the instrumental record was warmer than ~75% of the Holocene distribution. As described in the paper and its supplementary material, Figure 3 provides a reasonable assessment of the full range of Holocene global average temperatures, including an accounting for high-frequency changes that might have been damped out by the averaging procedure.

_________________With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none” Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."Albert Einstein

Note the rate of temperature change was the point of concern with the robustness of the data, not that the modern instrumental record compared to the reconstructed temperature record showed a change from the lowest temperature to nearly the hottest temperature during the past 11,300 years.

Q: Is the rate of global temperature rise over the last 100 years faster than at any time during the past 11,300 years?

A: Our study did not directly address this question because the paleotemperature records used in our study have a temporal resolution of ~120 years on average, which precludes us from examining variations in rates of change occurring within a century. Other factors also contribute to smoothing the proxy temperature signals contained in many of the records we used, such as organisms burrowing through deep-sea mud, and chronological uncertainties in the proxy records that tend to smooth the signals when compositing them into a globally averaged reconstruction. We showed that no temperature variability is preserved in our reconstruction at cycles shorter than 300 years, 50% is preserved at 1000-year time scales, and nearly all is preserved at 2000-year periods and longer. Our Monte-Carlo analysis accounts for these sources of uncertainty to yield a robust (albeit smoothed) global record. Any small “upticks” or “downticks” in temperature that last less than several hundred years in our compilation of paleoclimate data are probably not robust, as stated in the paper.

_________________With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none” Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."Albert Einstein

I think that the conclusions in the Marcott et al. 2013 should be revised to indicate that the 20th Century uptick that many blogs were concerned about was not statistically robust.

It's an interesting analysis for the Holocene Warm Period, but to focus on the 20th Century uptick of the reconstruction doesn't make much sense when the authors themselves confirmed that the uptick in the 20th Century was not statistically robust.

The reconstruction smoothing resolution would not have made it the best choice, but since we have instrumental records that cover the last ~150 years, well, there is no real need to worry with the reconstructed data at that point. If we had such instrumental data for the whole period we would not be dealing with reconstructions at all. Unless you are saying the reconstruction and instrumental records do not support each other in some manner?

Q: How do you compare the Holocene temperatures to the modern instrumental data?

A: One of our primary conclusions is based on Figure 3 of the paper, which compares the magnitude of global warming seen in the instrumental temperature record of the past century to the full range of temperature variability over the entire Holocene based on our reconstruction. We conclude that the average temperature for 1900-1909 CE in the instrumental record was cooler than ~95% of the Holocene range of global temperatures, while the average temperature for 2000-2009 CE in the instrumental record was warmer than ~75% of the Holocene distribution. As described in the paper and its supplementary material, Figure 3 provides a reasonable assessment of the full range of Holocene global average temperatures, including an accounting for high-frequency changes that might have been damped out by the averaging procedure.

Looking at the individual proxies gives a better idea with how uncertain the dataset is.

We can see here that the proxies are actually in wide disagreement with each other.

I think that the conclusions in the Marcott et al. 2013 should be revised to indicate that the 20th Century uptick that many blogs were concerned about was not statistically robust.

It's an interesting analysis for the Holocene Warm Period, but to focus on the 20th Century uptick of the reconstruction doesn't make much sense when the authors themselves confirmed that the uptick in the 20th Century was not statistically robust.

The reconstruction smoothing resolution would not have made it the best choice, but since we have instrumental records that cover the last ~150 years, well, there is no real need to worry with the reconstructed data at that point. If we had such instrumental data for the whole period we would not be dealing with reconstructions at all. Unless you are saying the reconstruction and instrumental records do not support each other in some manner?

Q: How do you compare the Holocene temperatures to the modern instrumental data?

A: One of our primary conclusions is based on Figure 3 of the paper, which compares the magnitude of global warming seen in the instrumental temperature record of the past century to the full range of temperature variability over the entire Holocene based on our reconstruction. We conclude that the average temperature for 1900-1909 CE in the instrumental record was cooler than ~95% of the Holocene range of global temperatures, while the average temperature for 2000-2009 CE in the instrumental record was warmer than ~75% of the Holocene distribution. As described in the paper and its supplementary material, Figure 3 provides a reasonable assessment of the full range of Holocene global average temperatures, including an accounting for high-frequency changes that might have been damped out by the averaging procedure.

Looking at the individual proxies gives a better idea with how uncertain the dataset is.

We can see here that the proxies are actually in wide disagreement with each other.

So call me skeptical about the Marcott et al. 2013 paper.

So you expect all locations around the globe to have the same temperature pattern and if they do not you disbelieve them? I suppose that tells us a lot about the science education in the US.

_________________With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none” Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."Albert Einstein

They claim that current warm temperatures in the Arctic regions are unprecedented over the last 600 years, which may or may not be true. The paper is behind a paywall, so I'm not able to access the full paper and see the data, so I'll remain neutral about this paper for now. It's also not surprising that it shows that the Arctic Temperatures are the warmest in 600 years, since the warming period in question, the MWP, was not included in the timeframe of analysis in the paper. My main interest is the causes of climate change over the last 150 years and how sensitive the climate is to an equilibrium doubling of CO2. The sharp warming over the last 150 years or so has likely had a significant solar component to the warming, even when assuming that the Hockey Stick Proxies are correct, like Usoskin et al. 2005 did.

Interestingly, they get a very nice correlation between solar activity and the temperature when they used mostly hockey stick reconstructions. Even more interesting is that Usoskin, Solanki and the other authors of the paper are proponents of the "mainstream" Anthropogenic Global Warming hypothesis. Yet, they found that solar activity can explain at least a sharp 0.3-0.4 Degree C increase (roughly) during this most recent warming episode.

The next image is from Scherer et al. 2006. This paper shows the intricate correlation between solar activity and temperature over the last 2000 years even more closely. Again, note the dramatic increase in solar activity over the 20th Century in Solar Activity.

Solar Activity rising substantially and pretty dramatically during the 20th Century can explain a large portion of the sharp warming during this period. Of course, while the anthropogenic contribution is also significant, the Solar Forcing is one that can not be ignored.

Last edited by Snowy123 on Wed Apr 10, 2013 9:57 pm, edited 3 times in total.